Safety device for brakes.



s. e. DOWN. SAFETY DEVICE FOR. BRAKES.

APPLICATION FILED MAR. 18, 1910.

Patented Jan. 6, 1,914.

Att'y.

WITNESSES CQLUMBIA PLANOGRAPH 60.. WASHINGTON, n. c.

UNITED STATES PATENT ornin.

SIDNEY G. DOWN, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE WESTINGHOUSE AIR BRAKE COMPANY, OEIPITELSBURGI-I, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA.

SAFETY DEVICE FOR BRAKES.

Application filed March 18, 1910. Serial No. 550,161.

To all whom it may concern:

Be it known that I, SIDNEY DowN, a citizen of the United States, residing at Chicago, in the county of OookandState of Illinois, have invented new and useful Improvements in Safety Devices for Brakes, .of which the following is a specification.

This invention relates to automatic fluid pressure brakes, and the principal object of the invention is to provide means enabling the engineer tocontrol the brakes in case it is found that the brakes can not be operated in the usual way by manipulation of the 'engineers brake valve to vary the train pipe pressure.

In the handling of trains equipped with fluid pressure brakes, it sometimes happens, for example, that an angle cock in the train pipe is left closed, or in some other way flow of air through the train pipe is prevented so that upon reducing the train pipe pressure to elfect an application of the brakes, no brake will be obtained on cars at the rear of the train pipe obstruction.

According to my invention, it is proposed to provide means adapted to be operated by variations in pressure in an additional pipe line, such as the train signal pipe, for producing a reduction in train pipe pressure, so as to efiect an application of the brakes, regardless of any obstruction in the train ipe. p In the accompanying drawing; Figure l is a central section of a preferred form of the fluid pressure brake safety device, and Fig. 2 a diagrammatic view of an engine brake equipment, showing the safety device applied thereto.

In its preferred form, the safety device may comprise, as shown in Fig. 1, a casing 1 having a chamber 2 in open communication with the signal line pipe 3. The pressure in chamber 2 acts on one side of a diaphragm 4:, the oppositeside being subject to the pressure of an adjustable spring 5. A valve 6 controls communication from the chamber 2 toa passage? leading to a piston chamber 8 and is adapted to be operated by the diaphragm 4. Within the chamber '8 is a piston or movable abutment 9 for operat- Specification of Letters Patent.

Patented J an. 6, 191a.

ing a valve stem 10 carrying a slide valve The valve chamber 12 of the valve 11 1s an open communication with the train pipe 13 and valve 11 is provided with a 'hrough port 14 adapted in one position of the valve to communicate with an atmospheric exhaust port 15. v

A coil spring 16 normally tends to maintain the slide valve 11 in its upper closed position and in order to prevent leakage from the train pipe around the valve stem 10, a seat gasket 17 may be provided on the stem 1"0 which is adapted to engage a seat 18. A lever 19 connected to valve stem m ls provided for operating the valve 11 manually.

On the locomotive, as shown in Fig. 2, the usual pipe connection 20 isuprovided containing the reducing valve device \21 and connected to the {main reservoir 22, so that the pressure may be normally maintained at a predetermined degree in the signal line pipe 3, and likewise, the usual signal valve device 23 is connected to the signal pipe. In addition to the above, a icy-pass pipe-24 is provided having a cook 25 and adapted to connect the main reservoir directly to the signal pipe 3.

In. operation, a safety device may be appliedto each car, but preferably is-only employed on the tail car, the same having connections to the train pipe 1'3 and signal pipe line 3, as hereinbefore described. The spring 5 is adjusted to a pressure exceeding the normal signal line pressure carried, by a certain amount, say by 10 pounds, for example, so that upon raising the signal line pressure 10 pounds above normal the fiuid pressure will overcome the pressure of the spring 5 and the diaphragm will be operated to open the valve 6 and admit fluid under pressure to the piston 99. The piston 9 is thereupon operated to shift the valve 11 and cause port 14 to register with eX- haust port 15, so that fluid is vented from the valve chamber 12 and the train pipe 13 to effect a reduction in train pipe pressure and the consequent application of the brakes. It will now be evident that when the engineer finds that he cannot operate the brakes in the usual manner by reducing the train pipe pressure it is only necessary for him to operate the cook 25 to admit fluid from the main reservoir to the signal line pipe. This higher than normal pressure in the signal pipe line then operates the safety device at the rear of the train to effect a reduction in train pipe pressure as above described.

With th present device, it is not necessary for the engineer to lose time signaling to the brakeman at the rear of the train to apply brakes as he can make an application directly through the signal pipe.

An equalizing port 26 may be provided through the piston 9, so that upon closing the cook 25 on the engine, the pressure in the signal pipe will fall by leakage through the port 26 until the pressure reduces sutliciently to permit the diaphragm I to seat the valve 6. The opposing pressures on the piston 9 then quickly equalize and the spring 16 operates to shift the valve 11 and cut off the further exhaust of fluid from the train pipe.

Should leakage occur through the signal line reducing valve 21, the pressure in excess of the degree at which the spring 5 is adjusted will escape past the valve 6 and through the port 20, which is made of such size as to take care of this leakage and thus prevent the movement of the piston 9.

The handle 19 is provided so that the train pipe pressure may be reduced by manual operation of the valve 11 when the brakeman at the rear of the train desires to eflect an application of the brakes.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is

1. The combination with a fluid pressure brake operating upon a reduction in train pipe pressure for eflecting an application of the brakes, of an additional pipe line and a valve device operated by varying the pressure thereon for effecting a reduction in train pipe pressure and a valve mechanism subject to the pressure in said additional pipe line for controlling the operation of said valve device.

2. The combination with a fluid pressure brake operating upon a reduction in train pipe pressure for efliecting an application of the brakes, of a signal pipe line and means operated upon an increase in signal line pressure for effecting a reduction in train pipe pressure.

3. The combination with a fluid pressure brake operating upon a reduction in train pipe pressure for effecting an application of the brakes, of a signal pipe line and means operated upon increasing the pressure in the signal pipe line above normal for effecting a reduction in train pipe pressure.

4c. In a fluid pressure brake, the combination with a train pipe, of an additional pipe line, a valve for controlling a train pipe vent port, a movable abutment operated by fluid pressure for actuating said valve, and valve means 0 3erat-ing upon an increase in signal line pressure for supplying fluid to said abutment.

5. In a fluid pressure brake, the combi nation with a train pipe, of a signal line pipe, a valve for controlling a vent port from the train pipe, a movable abutment having means for equalizing the pressures on opposite sides and operated by fluid pres sure for actuating said valve, and valve means operating upon an increase in signal line pressure for supplying fluid to said abutment.

6. In a fluid pressure brake, the combination with a train pipe, of an additional pipe line, a valve mechanism governed by the pressure in the additional pipe line for controlling a train pipe vent port, and manually operated means for also actuating said valve mechanism.

7 In an air brake mechanism comprising separate brake and signal pipes, the combination with the brake and signal pipes, of a discharge valve in communication with the brake pipe for setting the brakes, means actuated by increasing the signal pipe pressure above normal to operate the discharge valve, whereby an eiiective pressure may be maintained at all times for signaling purposes and means under the control of the engineer for varying the air pressure in the signal line.

8. In an air brake mechanism comprising separate brake and signal pipes, the combination with the brake and signal pipes, of a conductors emergency valve for applying the brakes, a tripping device cooperating with said emergency valve for operating the same and actuated by increasing the air pressure in the signal line above normal, and means under the control of the engineer for varying the air pressure in the signal line.

9. In an air brake mechanism comprising separate brake and signal pipes, the combination with the brake and signal pipes, of a discharge valve in communication with the brake pipe for setting the brakes, means operable to trip said discharge valve and actuated by increasing the signal line pressure above normal, means opposing the operation of said tripping means when the signal line pressure is at normal or less, and means controllable from the engine for varying the air pressure in the signal line.

10. In an air brake mechanism comprising separate brake and signal pipes, the combination with the brake and signal pipes, of an emergency Valve for applying the brakes, a tripping device cooperating with the emergency valve for operating the latter In testimony whereof I have hereunto set and actuated by increasing the air pressure my hand. in the signal line above normal means for returning the tripping device to its normal SIDNEY D position, and means controllable from the Witnesses:

engine for Varying the air pressure in the WM. M. CADY,

signal line.- A. M. CLEMENTS.

Copies of this patent may be obtained for five cents each, by addressing the Washington, D. 0.

Commissioner of Patents, 

